This invention relates to wireless digital data transmission.
Typical wireless digital data communication is affected between radio-frequency (RF) active transceivers contained in each of two communication devices. Each RF transceiver has a separate power source to produce the radio-frequency carrier waves used to transmit data to the other devices.
In a first aspect, the invention provides a wireless network for transmitting digital data. The network includes an active transceiver to transmit carrier waves at a succession of preselected frequencies and a transponder. The transponder transmits digital data to the active transceiver by partially reflecting the carrier waves.
In a second aspect, the invention provides a transceiver for digital data. The transceiver includes an antenna to transmit radio-frequency (RF) carrier waves and an RF module coupled to drive the antenna to produce the RF carrier waves. The RF module detects reflected portions of the produced RF carrier waves at the same time. The RF carrier waves have a succession of frequencies.
In a third aspect, the invention provides a method for wireless data transmission. The method includes transmitting radio-frequency (RF) carrier waves to a transponder at a succession of frequencies and receiving reflected portions of the RF carrier waves from the transponder. The reflected portions are digitally modulated.
In a fourth aspect, the invention provides a method of wireless digital communication. The method includes receiving a first radio-frequency (RF) carrier wave at a receiver, digitally modulating an RF reflectivity of the receiver, and reflecting a portion of the first RF carrier wave in response to the digitally modulating of the RF reflectivity. The method includes repeating the receiving, digitally modulating, and reflecting for a second RF carrier wave at a new frequency.
Other features and advantages of the invention will be apparent from the following description and from the claims.